1. Field of the Invention
The present invention relates to ophthalmic surgical apparatus for vitreous surgery, and more particularly to apparatus for dissecting proliferative membrane of the retinal surface or adjacent ocular tissue.
2. Description of Related Art
Vitreous surgery is carried out to remove opacities out of the vitreous body thereby to reconstruct an optical path therein, and to excise proliferative tissue of the retinal surface which may cause retinal detachment so that retinal reattachment is achieved. Simple opacity excision can be performed relatively easily through the recent improvement of vitreous surgical apparatuses, instruments and techniques. Dissecting proliferative membrane from the retina, however, is considered as a surgery requiring the most difficult and highest skill in vitreous surgeries, because it needs delicate maneuvers within an extremely limited space inside an eyeball.
In a conventional basic operation to dissect proliferated membrane of the retinal surface, a hook, a pick and the like is inserted into an eyeball to hook a part of the proliferated membrane thereon and to remove the proliferated membrane off the retina while slowly raising it. In a case of strong adhesion of proliferated membrane to the retina, intraocular scissors may be used to cut the adhesion of the proliferated membrane.
Such a pick, a hook and the like requiring very fine handling, there were cases where an inexperienced surgeon stuck a pick too deep in the eyeball or hooked non-proliferated portions too much with the pick, and the retina of a patient was injured by mistake consequently.
And also, the surgery with pick resulted in cutting proliferated membrane off, could not raise it well. Surgeon therefore had to start over again hooking the proliferated membrane. When the proliferated membrane could not be dissected with only a pick according to situations of adhesion of the proliferated membrane, the surgeon had to exchange the pick for intraocular scissors and to insert it again into the eyeball. Consequently, there were some cases where the surgery took a very long time.